1. Technical Field
The present disclosure generally relates to methods for packaging light emitting diodes (LEDs), and particularly to a method for manufacturing LED packages wherein fluorescent material conformably and directly covers an LED die.
2. Description of Related Art
In recent years, due to excellent light quality and high luminous efficiency, light emitting diodes (LEDs) have increasingly been used as substitutes for incandescent bulbs, compact fluorescent lamps and fluorescent tubes as light sources of illumination devices.
Generally, an LED includes a substrate, electrodes arranged on the substrate, a reflective cup arranged on the substrate, an LED die arranged in the reflective cup and electrically connected to the electrodes, an encapsulation covering the LED die, and a fluorescent film coated on an outer surface of the encapsulation.
In the package of the LEDs, the fluorescent substance is firstly mixed in fluid encapsulating material, then the fluid encapsulating material is sprayed on the outer surface of the encapsulation, and finally the fluid encapsulating material mixed with fluorescent substance is solidified. However, during the spraying process, a sprayed area and a sprayed thickness of the fluid encapsulating material by the spray tool are difficult to control since the operation of the spray tool has a certain tolerance regarding, for example, the movement of the spray tool and the flow rate of the fluid encapsulating material. Therefore, the fluorescent film will be non-uniform in thickness. Further, the fluorescent substance suspending in the encapsulating material will deposit and undesirably cause a non-uniform distribution of the fluorescent substance in the encapsulating material. The uneven distribution of the fluorescent substance in the encapsulating material and the uneven thickness of the fluorescent film cause light generated by the conventional LED to have an uneven color distribution.
Therefore, what is needed is to provide a method for packaging LEDs which can overcome the above shortcomings.